National Stock Number (NSN) 5331-00-166-0975, or NIIN 001660975, (o-ring) was assigned November 19, 1971 in the Federal Logistics Information System (FLIS). This NIIN is Available for Manual Assignment. This NSN replaces 16 stock numbers. Five of the National Stock Numbers that it replaces are: 5330010350384, 5330007547444, 5330012761513, 5330000738160, 5330012772211.
There are 86 manufacturer part numbers associated with this NSN. 11 of those part number(s) are considered obsolete. The manufacturer part numbers were originally supplied by 32 suppliers. Today, 27 suppliers are listed as Active suppliers for this NSN. Of the active suppliers, 12 suppliers are deemed design controlled or valid supply parts. ISO Group has built a very strong supply chain for this NSN. We have direct relationships with 26 sources of supply.
This part number has not been procured by the US Government in over a year. There have been 28 contracts issued for this part number, with 29 awards given. There is minimal competition for this NSN. The US Government has awarded contracts to 5 different suppliers. The last contract numbers awarded were: SPE4A624FCAPB, SPE4A624FCAPB, SPE4A624FC2TK, SPE4A624FC2TK, SPE4A624FB52F. The total value of the awarded contracts has been US$ 60,728.30.
This NSN is very common among different weapons systems, belonging to 304 different platforms.
This national stock number is in high demand. Globally, demand for this NSN has originated from 21 countries. The 24 month forecast from the US Government for this part number has high volatility, with an estimated forecasted value of US$ 2,877. Based on a planned procurement review by the Primary Inventory Control Activity (PICA) on Apr 27, 2019, this NSN's acquisition method was noted as: Not established. Not established.
This NSN is assigned to Item Name Code (INC) 47946. [A NONMETALLIC CIRCULAR ITEM WITH AN APERATURE, HAVING A SOLID ROUND CROSS-SECTION. THEY ARE USED PRIMARILY FOR SEALING. FOR ITEMS WITH OTHER THAN ROUND CROSS SECTION, SEE PACKING,PREFORMED. FOR NONCIRCULAR ITEMS WITH A ROUND CROSS-SECTION, SEE SEAL,NONMETALLIC ROUND SECTION AND RUBBER,ROUND SECTION.]. This item does not have a nuclear hardened feature or any other critical feature such as tolerance, fit restriction or application. There is no data in the HMIRS and the NSN is in an FSC not generally suspected of containing hazardous materials. NSN 5331001660975 does not contain precious metals.
This NSN is associated to Schedule B 4016930000: gaskets, washers and other seals, of vulcanized rubber other than hard rubber. The Schedule B End Use is listed as industrial rubber products. NAICS classification category 339991: gasket, packing, and sealing device manufacturing.
This information was last updated on Jul 01, 2026.